Seam detector



sePt- 19, 1950 H. w. BEALL 2,523,184

sEAM DETEoToR Filed May 6, 1949 2 Sheets-Sheet l ATTORNEY H. W. BEALLSEAM DETECTOR sept. 19, 195o 2 Sheets-Sheet 2 Filed May 6, 1949 I N VENTOR. /efiwell Patented Sept. 19, 1950 SEAM DETECTOR Herbert W. Beall,Lancaster, S. C., assignor t The Springs `Cotton Mills, Lancaster, S.C., a corporation of South Carolina Application May 6, 1949, Serial No.91,829

2 Claims. l

My invention relates to a seam detector for use in connection with thehandling of long lengths of cloth that are made up by joining shorterlengths by sewing a seam across the run of the cloth thereby joiningadjacent end portions. These seams may be lapped seams or at seams ormixed. In tearing these long lengths into shorter lengths to makesheets, etc., it is desirable to `arrange the varying lengths of clothinto which sheets may be made so as to make the seam fall near oradjacent the end of a sheet so that the seam may be torn out with theminimum of waste.

In order to avoid such Waste it is necessary to Warn the operator sometime in advance of the approach of a seam. It is therefore customary toprovide a maze through which the cloth passes and which will hold adefinite length of cloth so that the operator may be informed of thenumber of the various lengths of sheets that can be torn, and have theseam fall adjacent the last sheet. It is not possible to do this unlessthe sheets vary in standard lengths, such as 108", 99" and 90". Forinforming the operator of the approach of a seam it is usual to use aseam detector with a signal device or a trip mechanism that stops amotor and so to stop the feeding of the cloth.

My present invention is an improvement on present seam detectors. runone layer of cloth through the detector it is often desirable to use thedetector on folded cloth where two or more layers pass through thedetector.

It is an object of my invention to provide a seam detector which willoperate on multiple layers of cloth.

Another object is to provide easy and accurate means for adjusting thegap in the detector even while the cloth is in motion, if desired.

Another object is to provide an indicator to assist in setting the saidgap in the detector, through which the cloth travels.

Another yobject is to provide means for preventing tears in the clothwhen a slub or thick place in the cloth comes into contact with thepoints.

Another object is to provide means for easy insertion of the clothbetween the points of the seam detector.

Referring now to the annexed drawings, which are made a part of thisapplication and in which similar characters of reference indicatesimilar parts:

Fig. 1 is a perspective of a length of cloth Although it is usual to 2having portions connected at their adjacent ends by means of seams andalso having diagonal wrinkles.

Fig. 2, a transverse section of the machine, showing my improveddetector in position thereon,

Fig. 3, a wiring diagram,

Fig. 4, a top plan of a screw shown in Fig. 2,

Fig. 5, a side View of a modification, and

Fig. 6, a detail of a feeler forming part of the same, on an enlargedscale.

In the drawings, reference character I0 indicates a folded sheet ofcloth comprising a plurality of loom lengths connected at adjacent ends,preferably by conventional fiat butt seams Il, such as are made byWilcox & Gibbs sewing machines and others for connecting edges of clothwithout forming thick seams, which are undesirable for various reasons.If the cloth is moving in the direction of the arrow in Fig. l, wrinklesor folds such as are indicated at I2 will be formed therein. A seamdetector including clothengaging renewable wear buttons I3, I3, ispositioned crosswse of' the strip of cloth, as indicated in Fig, l,these buttons being made of hard rubber, or suitable plastic or othermaterial. In the form of the invention here disclosed the buttons aremounted upon reduced lower end portions of rods I4 and are so located asto press the upper surface of the cloth, against a pressure bar I4attached to a fixed part I4 of the machine.

The essential feature of the invention consists in the use of aplurality of feelers in a rowcrosswise of the cloth or nearly in a row,the actual preferable number being dependent on the width of the cloth,the weight of the cloth, etc. Each feeler includes a button, a switchmember, and means for supporting them in constant relation to oneanother or substantially so. As stated, the number of feelers dependssomewhat on the characteristics of the cloth to be torn, for the bestresults, but what is essential is that there shall be a plurality ofsuch feelers if multiple layers of cloth are being operated on.

It is obvious that when only one feeler is used in a transverse row adiagonal Wrinkle or fold will be just as effective to operate the feeleras a sewed seam provided that the wrinkle stands up suiiiciently abovethe level of the cloth, though a single feeler may be effective underconditions discussed hereinafter. With my new arrangement of a pluralityof feelers in a row actuation of a single feeler will have no stoppingor signaling effect; only upon actuation of all the feelers in a rowwill stopping or signaling be effected.

The rods I3 and their buttons are preferably three in number for anyordinary conditions and the rods are mounted for vertical slidingmovement in bearings I5 on the bottom member I6 of a casing which isshown as enclosing the principal parts of the seam detector. A bar I1 isfixed in place in an upper part of the casing, and the rods I4 arearranged to slide in apertures in the bottom of the casing and in barI1. Springs I8 surround the respective rods I4, said springs bearing attheir upper ends against bar I1 and at their lower ends against collarsI9 on portions of rods I4, the adjustment of said col-- lars varying thecompiession of the springs and so varying theii resistance to upwardmovement of the respective rods. The springs press the buttons downagainst the cloth and the bar I4.

At. their upper ends the rods I4 are provided with collars 2l!` thatsupport rings 2| of electrically conductive material. Blocks- 22 mountedon the bar I1 support contacts 23, 24 for engagement with rings 2I, thecontacts 23 being in permanent engagement with their rings and thecontacts 24 being resilient and being normally spaced apart from suchrings to an extent that is predetermined in accordance with thenecessitiesof the particular machine or the cloth passing through it fortearing into lengths or for any other purpose.

The adjustment of the movable contacts is effected by means of screws 25having threaded engagement with nuts 25 that may be formed integrallywith the casing of the detector, and ga locknut 25 is provided upon eachscrew for hold-ing it in adjusted position. Screws 25 have insulatingpads 25a at their lower ends and extend outside the casing. Thus theycan be adjusted whether the machine lis running or not. It will be lseenthat the screws can all be adjusted by the help of a neonvlamp togetherwith the seal-e marks on the heads of the screws and a unit mark on anadjacent xed surface so as to close the contacts. and that byappropriate manipulation each. screw may beset so as to hold its contact24 very exactly at the amount of opening suited .for .moving its circuitcloser upon occurrence of a seam in cloth of the weight and thicknessbeing handled. Conventional conductors 28, 29 carry. current to thevcontacts above mentioned.

Switches 30, 3U, 3l]A are provided to short circuit two of the pairs ofpoints, while the other is being adjusted. For instance, two switchesare first closed and the other two points are then also closed byturning down their screw 25 until the neon lamp goes out, as the currentnow passes through the points. The screw is now turned counterclockwiseuntil the lamp again lights up, and the screw is turned a smalladditional amount to clear thick places such as may occur in the cloth.This additional amount may be determined by means of the reference marksshown in Fig. 4. The other points are adjusted in like manner by openinganother switch and closing the one that was previously opened.

When the points are closed the current flows through the solenoid whichinterrupts the motor circuit, or a relay that operates a signal devicesuch as a bell, a light, etc. Since the seam passes the detector veryquickly it is not practical to rely on seeing a signal or hearing asignal and then stopping the machine manually, but it is necessary touse an automatic trip which is afterward reset manually or elseautomatically at the end of a cycle. Such a trip is shown at 33a.

The seam detector may be used in a cloth tearing machine of the typedisclosed in my patent application Ser. No. 779,513, filed October 13,1947.

The buttons I3, I3 are pressed against the cloth bythe springs I8, I8,the cloth being supported by the pressure bar I4', as above stated. Themovement of the buttons is from .004" to .015 when raised by a passingseam, the amount of the lifting depending on Whether the seam is alapped seam or a butt seam. The feelers are in series with each otherand with the relay. If only one of the detectors is raised to cause itscontacts to engage, as by a diagonal fold or wrinkle, the rod Willsimply descend to its original position after the fold has passed, butif all the detectors of a row are raised by a transversely extendingseam the relay shown at 33 will be energized, breaking the motor circuitof motor 32, and the motor will stop runtil the relay is reset, it beingunderstood that the relay remains open until reset manually or byautomatic action at the end of a cycle. At this time the signal lampwill be short circuited and the light will go oii iand on very quickly,i. e., for about 1/50 second. When the seam has been moved past thedetectors they descend and the lamp lights up again but the relay willremain tripped.

Since the adjustment of the detectors must be very accurate, as formultiple folds of thin cloth, I provide very accurate means for makingthe adjustments above described. A detail of a modified Ipush rod isshown in Fig. 6. In this form it comprises a hollow stem 43 and atelescoping upper shaft 41 that is slotted at 46 near its lower end toreceive a pin that extends across the hollow stem. A spring 58 urges theshaft 41 upward so far as permitted by the pin, after which the entirepush rod is forced upward by irregularities in the cloth to force thecontact 49 against contact 50. If the irregularities are abnormally highspring 58 will yield, allowing the cloth to pass without tearing it. Acollar 44 on the hollow stem prevents the stem from falling through itshole in the casing when the device is being assembled and also takes thepressure of the spring, if a spring is used to produce pressure on thecloth, The collar never touches the casing unless the detector unit isbeing taken apart, but is held up by the cloth and forced down by thespring against the cloth if there is cloth in the machine. The contactsprings 50 may be made strong enough to press the buttons against thecloth, if desired.

The bracket 34 supports a box consisting of an upright 39, horizontallyextending members 31 and 38 parallel to each other, an outer end upright40 and a removable top cover supported on upwardly extending portionsofthe end members 39 and 40 by means of screws 42, 42. The 1ntermediatehorizontal bar 38- has a bearing in line with that in lower bar 31 forthe push rod, which member also limits the movement of the push rod byengaging the collar 44, and the bar 38 supports a block 5I for carryingthe resilient contacts 49 and 50, which are attached to conductors 52 ina socket 53 that has a neon lamp mounted therein, and conductors 54leading to a control means, as in Fig. 3, Means for adjusting the uppercontact 50 relatively to the lower contact 49 consists of a screw 55adjustably mounted in a fixed nut 56, and a locknut 51. The screw has aninsulating pad 55' at its lower end t0 engage the upper contact, and asthe screw extends outside the casing the contacts can be manipulatedwhether the machine is running or not.

The head of the hollow stem constitutes the cloth-engaging button, andis shown as integral with the hollow stem, but may be removablyattached, as in Fig. 2. An insulating plug 48 is mounted in a recess atthe upper end of the push rod.

The relay is in circuit with the contacts 49 and 50 and when they arebrought together the solenoid will be energized so as to close the relayand stop the motor until the relay is reset. Impedance of the relay issuch that a normal amount of current passes through the contacts. Whenthe neon lamp is connected across the contacts it will light up withoutenergizing the solenoid, since its resistance is very high. If thepoints are now brought together the neon light will go out and the relaywill be energized to break the motor circuit. No current can flowthrough the neon light at this time since it is short circuited due tothe fact that the -contacts 49 and 50 are engaged t0 close the circuitat that point.

To set the button so that it will press the face of the cloth, While yetthe contacts are open, the screw 55 isrotated to bring the contactstogether. The light now is extinguished. When the screw is backed oiuntil the position of the contact is such that it just permits the lightto go on again a small additional movement of the screw will set thebutton `at the most advantageous level.

It will be obvious to those skilled in the art that many changes may bemade in the devices herein disclosed, all without departing from thespirit of the invention; and therefore I do not limit myself to what isshown in the drawings and described in the specification, but only asindicated in the appended claims,

Having thus fully described by invention, what I claim is:

1. Means for detecting a seam in a traveling strip of material,comprising a plurality of circuit closers arranged in a linesubstantially across the path of the strip, and means operable only uponsimultaneous closing of all the circuit closers for indicating theoccurrence of a seam.

2. A seam detector for sheet handling devices, comprising a supportingmember over which the material travels, a plurality of feelerscontacting the material and arranged in a series extending transverselyof the travel of the material, and an electric circuit including aplurality of contacts in series said contacts being operable by saidfeelers.

HERBERT W. BEALL.

REFERENCES CITED The following references are of recordin the file ofthis patent:

UNITED STATES PATENTS Number Name Date 869,324 Obert Oct. 29, 19071,149,018 Beregh Aug. 3, 1915 2,091,522 Perry Aug. 31, 1937 2,402,312Burch June 18, 1946

